Switch assembly



April 29, 1958 ca. w. JONES swrrcn ASSEMBLY Filed Oct. 10, 1956 Anvenl'ot @mcdd W? Jones United States Patent SWITCH ASSEMBLY Gerald W. Jones, Newton, Iowa, assignor to The Maytag Company, Newton, Iowa, a corporation of Delaware Application October 10, 1956, Serial No. 615,131

12 Claims. (Cl. wo -s This invention relates generally to a novel cam operated switch assembly in which a revoluble cam controls the positioning of switch follower member constituting the movable part of an electric switch. It is specifically directed to an electric switch capable of electrically connecting one switch conductor to either, neither or both of two other separate switch conductors.

Common switch constructions of the past have included a type of switch in which a cam follower provided with a pair of contacts on its opposite sides was resiliently urged toward a revoluble cam having cam lobes located on three separate elevational levels to thereby move the resilient follower into three positions against either or neither of two electrical contacts adjacent the follower. By that construction a circuit could be completed from the conductor connected to the follower to either of the two separate conductors respectively attached to those adjacent switch contacts. That prior construction did not, however, have the additional feature in which the electrical circuits through both adjacent switch contacts could be energized simultaneously since the switch follower member was incapable of being placed in more than one position at a time. It is toward this desirable feature that this instant invention is directed.

The simultaneous making of two separate circuits by a single switch follower is achieved by providing a twosectioned switch follower responsive to four separate elevational levels of cam lobes provided on the actuating cam. At the first three elevational levels of the cam lobes, electrical contact is made from the follower to either or neither of the two contacts adjacent the switch follower similar to the action of the previously mentioned switch construction. However, in the fourth position, the two-sectioned follower splits in such a manner as to cause electrical contact to be made simultaneously from the switch follower to both of the two adjacent switch contacts to thereby effect a simultaneous energiza tion of two separate circuits.

By this construction disclosed hereinafter in greater detail extra cams and switch followers may be eliminated to thereby reduce not only the cost of the switch assembly but also to reduce the amount of space necessary to house an automatic timer or sequential controller of the type used in domestic appliances operating over controlled, timed cycles of operation.

in the accompanying drawings:

Figure 1 is a side elevation, partially broken away, showing an automatic timer embodying my invention;

Figure 2 is a perspective view of a two-sectioned switch follower assembly forming a part of the timer shown in Figure 1;

Figure 3 is a sectional view taken on line 33 of Figure 1 showing the switch follower assembly in its outthrown position;

Figure 4 is a view similar to Figure 3 showing the actuating cam rotated 90 clockwise from that of Figure 3 to position the switch follower assembly in its no-contact position;

2,832,851 Patented Apr. 29, 1958 "ice Figure 5 is a view similar to that of Figure 4 showing the actuating cam rotated 90 clockwise from that of Figure 4 to place the switch follower assembly in its in-throw position;

Figure 6 is a view similar to that of Figure 5 showing the actuating cam rotated 90 clockwise from that of Figure 5 to thereby place the switch follower assembly in its combination double-contact position;

Figure 7 is a perspective view of the pivoted section of the switch follower assembly; and,

Figure 8 is a fragmentary perspective view of the main portion of the switch follower assembly.

Referring now to the accompanying drawings, Figure 1 shows the timer assembly embodying my invention as being powered by a constant speed motor 10 which, through the speed reduction unit 11 and conventional one-way drive (not shown), drives the timer rotor shaft 14.

Rotor shaft 14 extends through the front and rear timer housing plates 15 and 16, respectively, and is afiixed to the manually adjustable control knob 17 positioned adjacent the cabinet panel 18 on which the timer assembly may be mounted.

The front and rear timer housing plates 15 and 16 are joined at their ends by insulated terminal side boards 21 and 22, which together with plates 15 and 16, form a housing for the timer cams 24, 25, 26 and 27 which are fastened on the timer rotor shaft 14. Spacer members 28 mounted on and concentric to timer shaft 14 maintain these cams in spaced relation from each other.

Each of these timer cams 24, 25, 26 and 27 is provided with a switch follower 31, 32, 33 and 34, respectively. Each of these switch followers is riveted to terr minal board 21 and, in this embodiment, resiliently trated in Figure 1, reference need be made only to one of these cams, for example, cam 24, together with its unitary switch follower assembly 31 to adequately describe my invention.

In the accompanying drawings, timer cam 24 is shown provided with four lobes 36, 37, 38 and 39 which are positioned on four dilferent elevational levels at different radial distances from the rotational axis of timer rotor shaft 14.

While switch follower assembly 31 is connected to the terminal board 21 by a single rivet connected electrically to the switch conductor 41, it will be seen that the switch follower 31 is actually formed from two separate sections 31 and 31 The main portion 31 constitutes that part of switch follower 31 connected to terminal board 21 and is provided with upstanding side flanges 44 to strengthen that portion containing the aperture 45 through which the pivoted second portion 31 extends to contact, by means of its tang 46, the revoluble actuating timer cam 24.

Pivoted portion 31 is provided with a pair of trunnions 48 which are positioned within oppositely positioned notched portions 49 located in the lower portions of the upstanding side flanges 44. These trunnions 48 are parallel and adjacent to the upper edge 50 defining the side of aperture 45 closest to the contact 51 located on the free end of the main follower portion 31,,. This construction permits the pivoted portion 31 to be restrained within notches 49 and still pivot about edge 50 (Figure 8). Other equivalent constructions permitting similar pivotal movement of portion 31 relative to portion 31,, may also be used. I

Contact 51 is adapted to engage the lower contact 52 located on terminal board 22 and connected to conductor 58 whilethe pivoted portion 31 is provided with a contact 53 which is engageable with the upper contact 54 located on the terminal board 22 and connected to a third conductor 59.

From this is will be seen that pivoted portion 31,, may be positioned in either a back-to-back relation relative to main portion 31 as shown in Figure 5, for example, or in a split position relative to that main portion as shown in Figure 6. The force acting to position portions 31 and 31, in an abutting or back-to-back position by rotation of the pivoted member 31 in a clockwise direction relative to main portion 31 is determined by the force acting on tang 46 while the force tending to separate portions 31,, and 31, by movement of the pivoted portion 31 in a counterclockwise direction is determined by the action of a leaf spring member 56 riveted to the main portion,31 andspressing downwardly on portion 31,,. Since the force ofsthe spring 56 is opposed by the force acting on the tang 46, the positioning of the pivoted member 31 relative to portion 31 is determined by the algebraic summation of the moments produced by these forces about the trunnions 48 on the pivoted member 31 .In the operation of this switch assembly, clockwise rotation of the timer rotor shaft 14 and the timer cam 24 may be achieved by either a manual rotation of the control knob 17 or by action of the timer motor 10. When the timer cam 24 is positioned as shown in Figure 3 with the lobe 36 pressing against the tang 46, the main portion 31, is forced by reason of its abutting or backto-back relationship to portion 31 to move contact 53 against the upper contact 54. Since there is an electrical contact at all times between portions 31 and 31,,, an electrical circuit is completed between the switch conductor 41 and the switch conductor 59 connected to terminal board 22. In this position, the force produced by leaf spring 56' against the pivoted portion 31, is insufiicient to split the portions 31,, and 31 It should be noted here that if the pivotal portion 31 is subjected to relatively high current requirements; it may be desirable to guarantee its constant connection to main portion 31,, by providing a flexible jumper between these parts.

When the timer cam 24 is rotated 90 clockwise from itsjposition in Figure 3 into its position shown in Figure 4, the resiliency of the main portions 31 causes that portion to separate from the upper contact 54., Whenithe switch follower assembly 31 is in this position, the force exerted by timer cam 24 against tang 46 is still great enough to produce a moment tending to keep portions 31,, and 31, in a back-to-back position.

When timer rotor cam 24 is moved 90 further in a clockwise direction into the position shown in Figure 5, the resiliency of the main portion 31,, causes its contact 51 to engage the lower contact 52 and thereby complete an electrical circuit from conductor 41 to the opposite conductor 58 connected to terminal board 22. position of cam 24, the force produced by leaf spring 56 is still insufficient to produce a counterclockwise movement of the pivoted member 31 relative to the main portion 31,.

When the timer rotor cam 24 is moved 90 further from the position shown in Figure into that shown in Figure 6, the main portion 31,, remains in the position in which its contact 51 engages the lower contact 52. In this position of cam 24, tang 46 is not urged against timer cam 24 by the resiliency of portion 31 but is pressed against that timer cam 24 by the end of the leaf spring 56 which causes the pivoted portion 311; to pivot in a counterclockwise direction about edge 50 until contact 53 engages the upper contact 54 to provide a stop for this pivotal movement. This movement of pivoted portion 31,, causes an electrical circuit to be established between switch conductor 41 and both switch conductors 58 and 59 to thereby energize two separate circuits through these three conductors. The energization of these separate circuits would be substantially simultaneous if actuating In this 4 a cam 24 were moved from its position of Figure 4 to that of Figure 6.

While the timer assembly disclosed herein has been illustrated as progressing over four separate progressively decreasing cam levels, it should be obvious that the progression of these cam levels may be varied to accommodate various circuitry requirements. It should also be apparent that while all three cam levels shown in Figures 3, 4 and 5 were used in conjunction with the cam level shown in Figure 6, the cam level of Figure 6 may be selectively utilized with one, two or three of the other cam levels as desired.

It will be seen from this operational description that this type switch assembly is capable of completing a circuit between conductors 41 and 58 separately or between conductor 41 and conductor 59 separately or between conductor 41 and both conductors 58 and 59 simultaneously or to break connections between 41 and both of those conductors 58 and 59 if so desired.

While the actuating cam shown in the accompanying drawings is of the rotary type, it is within the spirit of this invention to provide other forms of actuating cams including sliding or tanslatory type cams.

I claim:

1. A switch assembly comprising, an actuating cam, a first member biased toward said cam, a follower member pivoted on said first member and engageable with said cam, a first contact on said first member, a second contact on said follower member, said follower member serving as a reaction member opposing the bias of said first member and tending to maintain said first and second contacts in a back-toback position, means engageable with said follower member tending to separate said contacts, first and second conductor means positioned adjacent first and second contacts, and means on said cam for moving said first member between said first and second conductor means for selectively separating said first and second contacts and moving said contacts against said first and second conductor means respectively.

2. A switch assembly comprising, an actuating cam, a first member resiliently biased toward said cam, a follower member pivoted on said first member and engageable with said cam, a first contact on said first member, a second contact on said follower member, said follower member serving as a reaction member opposing the bias of said first member and tending to position said follower member in an abutting relationship with said first member, meansengaging said follower member and tending to pivot said follower member relative to said first member, first and second conductor means positioned on opposite sides of said first member for engagement with said first and second contacts, and means on said cam controlling movement of said first member and pivotal movement of said follower member relative to said first member.

3. A switch assembly comprising, a cam follower assembly having separable first and second contacts thereon, first and second conductor means positioned adjacent to said cam follower assembly, an actuating cam movable relative to said cam follower assembly and having a first portion engageable with said cam follower assembly to position said first contact against said first conductor means, a second portion on said cam engageable with said cam follower assembly for positioning said cam follower assembly intermediate of said first and second conductor means to prevent electrical contact from being made from said cam follower assemblyto either of said conductor means, a third portion on said cam for positioning said second contact against said second conductor means, and a fourth portion on said cam for simultaneously positioning said first contact against said first conductor means and for positioning said second contact against said second conductor means.

4. A switch assembly comprising, a cam follower as T sembly having separable'first and second contacts thereon,

assess-1 first and second conductor means positioned on opposite sides of said cam follower assembly, an actuating cam movable relative to said cam follower assembly and having a first cam portion engageable with said cam follower assembly to position said first contact against said first conductor means, a second cam portion on said cam for positioning said cam follower assembly in a position intermediate of said first and second conductor means to prevent electrical contact from being made from said cam follower assembly to either of said conductor means, a third cam portion on said cam for positioning said second contact against said second conductor means, and a fourth cam portion on said cam engageable with said cam follower assembly for separating said first and second cam contacts to position said first contact against said first conductor means and simultaneously position said second contact against said second'conductor means.

5. A switch assembly comprising, a cam follower assembly having first and second separable contacts thereon, first and second conductor means positioned adjacent said cam follower assembly, an actuating cam movable relative to said follower assembly and having a first cam portion engageable with said cam follower assembly for positioning said first contact against said first conductor means, said actuating cam further including a second cam portion engageable with said cam follower assembly for positioning said second contact against said second conductor while maintaining said first contact in engagement with said first conductor means.

6. A switch assembly comprising, a cam foilower having first and second separable contacts thereon, first and second conductor means positioned on opposite sides of said switch follower assembly, an actuating cam movable relative to said follower assembly and having a first cam portion engageable with said cam follower assembly to position said cam follower assembly in spaced relationship to both of said first and second conductor means, said actuator cam further including a second cam portion for simultaneously positioning said first contact against said first conductor means and said second contact against said second conductor means.

7. A switch assembly comprising, a cam follower assembly having first and second separable contacts thereon, first and second conductor means positioned adjacent said cam follower assembly, an actuating cam movable relative to said follower assembly and having a first cam portion engageable with said cam follower assembly to position said second contact against said second conductor means, said actuating cam further including a second cam portion for moving said first contact against said first conductor means While maintaining said second contact in engagement with said second conductor means.

8. A switch assembly comprising, an actuating cam, a first member resiliently biased toward said cam, a follower member engaging said cam and pivoted on said first member, said follower member being urged into an abutting relationship with said first member by the bias of said first member, a bias member engaging said follower member and tending to pivot said follower member relative to said first member, first and second electrical conductor means positioned on opposite sides of said first member and limiting the travel of said first member toward and away from said cam, means on said cam for selectively positioning said first member between said first and second conductor means, said cam further including a recess for receiving said follower member to pivot said follower member relative to said first member in response to the bias of said bias member when the travel of said first member relative to said cam is limited by one of said first and second conductor means.

9. A switch assembly comprising, an actuating earn, a first member resiliently biased toward said cam, a follower member pivoted on said first member, said follower member engaging said cam and being urged into an abutting relationship with said first member by the bias of said first member, biasmeans engaging said follower member and tending to pivot said follower member relative to said first member, first and second conductor means positioned on opposite sides of said first conductor and'limiting the travel of said first conductor toward and away from said cam, one of said first and second conductor means further limiting pivotal movement of said follower member relative to said first member, means on said cam for selectively positioning said first member between said first and second conductor means, said cam further including a recess for receiving said follower member to pivot said follower member relative to said first member in response to the bias of said bias means to position said follower member in electrical contact with one of said first and second conductor means while simultaneously positioning said first member in electrical contact with the other of said first and second conductor means.

10. A switch assembly comprising, an actuating cam, a first member resiliently biased toward said cam, an aperture in said first member, a follower member pivoted on said first member and extending through said aperture to engage said cam, spring means interconnected between said first member and said follower member to pivot said follower member relative to said first member, first and second electrical conductor means positioned on opposite sides of said first member and limiting the travel of said first member toward and away from said cam, one of said first and second conductor means further limiting pivotal movement of said follower member relative to said first member, means on said cam for selectively positioning said first member between said first and second conductor means, said cam further including a recess to receive said follower member to per mit said spring means to pivot said follower member relative to said first member and into electrical contact with one of said first and second conductor means.

11. A switch assembly comprising, an actuating earn, a first member resiliently biased toward said cam, an opening in said first member, a follower member pivoted on said first member and extending through said opening to engage said cam, spring means interconnected between said first member and said follower member to pivot said follower member relative to said first member, first and second electrical conductor means positioned on opposite sides of said first member and limiting the travel of said first member toward and away from said cam, one of said first and second conductor means further limiting pivotal movement of said follower member relative to said first member, means on said cam for selectively positioning said first member between said first and second conductor means, said cam further including a recess to receive said follower member and permit said spring means to pivot said follower member relative to said first member and simultaneously establish electrical contact from said first member to both of said first and second conductor means.

12. A switch assembly comprising, an actuating cam, a first member resiliently biased toward said cam and provided with oppositely positioned notches, an aperture in said first member adjacent said notches, a follower member provided with oppositely projecting trunnions positioned in said notches, said follower member extending through said aperture in said first member to engage said earn, a leaf spring member connected to said first member and engaging said follower member to pivot said follower member relative to said first member about an edge defined by said aperture and positioned immediately adjacent said notches, first and second electrical conductor means positioned on opposite sides of said first member, said first and second conductor means limiting movement of said first member relative to said cam and pivotal movement of said follower member relative to said first member, means on said cam for positioning a7 7.8 said first member between said first and second conduc- References Cited in the file of this patent tor means, said cam further including a recess for re- UNITED STATES PATENTS ceivmg sa1d follower member to permit sa d leaf spnng 7 member to pivot said follower member relative to said 1,947,332 chnsten 1934 first member to establish electrical contact from said first e 2'424116 Puemcr July 15, 1947 0 member to both of said first and second conductor means. 215031862 Angeyery P 1950 

